The manufacture of electrical circuits typically includes the depositing of a pattern of conductive lines and pads on a dielectric substrate. Several separate layers may be laminated together to form an electrical circuit board. Alternatively, an electrical circuit board may be produced by forming subsequent layers in a build-up type process. Typically, one or more substrate layers is provided with an alignment target that is employed as a reference in order to place respective substrate layers in mutual registration or to align via holes, which are drilled in the substrate, to patterns formed on the substrate layers. Alignment targets typically are embedded between various substrate layers. In order to employ a target in an alignment process, it is necessary to ascertain the location of the target.